The fact that they're much bigger than when they first met eight years ago is undeniable. Both Manny Pacquiao and Juan Manuel Marquez have added bulk along with the pounds, and both have had to deal with those who suspect they didn't do it naturally.

The fighters aren't the only thing that's grown. So have the purses and the attention as they meet Saturday night for the fourth - and presumably last - time in a rivalry that has served both fighters so well.

Marquez will try once again to do what he hasn't been able to do in 36 evenly contested rounds against Pacquiao - get a decision from the ringside scorecards. At the age of 39, it's a fight that may mean more to his legacy than his future career, which is why it's a fight he seems almost desperate to win.

"All I ask is for the judges to be objective," Marquez said. "They need to really see what is happening in the ring instead of what they think might be happening in the ring."

Pacquiao is not as desperate, but he needs a win just as badly. He barely escaped with a majority decision over Marquez in November 2011 and lost a widely panned decision to Timothy Bradley his last time out.

A loss to Marquez would not only confirm the whispers that he is slipping after 17 years as a pro, but perhaps derail for good any talk of a fight against Floyd Mayweather Jr.

"I have always been focused, but not like this fight," Pacquiao said. "There are no distractions in my mind. The family problems I had I don't have this time."

Neither fighter holds a title as they meet in a welterweight fight that will make both even richer. Pacquiao is expected to make more than $20 million by the time the pay-per-view receipts are totaled, and promoter Bob Arum said Marquez could make as much as $6 million.